The field of wireless communications encompass a variety of products, including personal devices such as pagers, cellular phones, and PCS phones, and information systems, such as wireless LANs (local area networks) and smaller wireless office networks. These products are widely used due to their convenience and comparatively low cost.
To maximize usage of the available bandwidth, a number of multiple access technologies have been implemented to allow more than one subscriber to communicate simultaneously with each base transceiver station (BTS) in a wireless system. These multiple access technologies include time division multiple access (TDMA), frequency division multiple access (FDMA), and code division multiple access (CDMA). These technologies assign each system subscriber to a specific traffic channel that transmits and receives subscriber voice/data signals via a selected time slot, a selected frequency, a selected unique code, or a combination thereof.
FDMA systems include frequency-hopped communication systems, in which the frequency spectrum is broken into channels that are small sub-spectrums. A transmitter and receiver pair can establish a communication link over a channel while other transmitter-receiver (TX-RX) pairs can use other channels. The channels selected by the TX-RX pair are chosen pseudo-randomly, typically based on a common time reference and the address (i.e., telephone number) of the receiver. For subsequent messages, new channels may be selected.
Mobile stations, such as cellular telephones, PCS handset devices, portable computers, telemetry devices, and the like, frequently operate from an external power source connected to the mobile station, with an internal battery supply being available to provide a limited period of operation without the external power source. Mobile stations which provide more extended intervals of battery back-up operation offer increased value of service to users and competitive advantages for service providers.
A mobile station enters the idle state when the mobile station is turned ON, is synchronized with the system, and has no calls in progress. During the idle state, a mobile station actively listens to a paging channel for information which includes overhead messages, such as system parameter messages, as well as messages directly addressed to the mobile station from a base station. Unfortunately, a mobile station operating on battery when it is in the idle state continues to drain the battery, even though the user does not make any effective use of the device.
Therefore, there is a need in the art for improves wireless devices that consume less power. In particular, there is a need for portable wireless mobile stations that consume less battery power. More particularly, there is a need for portable wireless mobile stations that consume less battery power when operating in an idle mode.